有机高分子链内的场致激子解离

基于SSH(Su-Schrieffer-Heeger)模型，采用静态及动力学自洽算法模拟了有机高分子链内激子在光激发及外电场作用下的形成与解离过程。结果表明，受光激发后，有机高分子链内激子的生成与解离密切依赖于施加外电场的时机，当外电场与光激发同时发生时，激子能否生成完全取决于电场强度的大小；而当外电场在光激发后的一段时间(通常为皮秒量级)之后被引入，则在有机高分子链内能够形成稳定的激子，且该激子只有在强外电场(超过1MV/cm)的作用下，才会发生解离，临界场强量级与实验结果相符合。

Electric Field Induced Exciton Dissociation in Organic Polymer Chains

Based on SSH (Su-Schrieffer-Heeger) model combined with both the static and dynamical evolution methods in the self-consistent formalism, the exciton formation and dissociation are investigated after photoexcitation and in the presence of an external electric field in an organic polymer chain. It is shown that, after photoexcitation, the processes of exciton formation and dissociation in a conjugated polymer chain is closely dependent on the occasion when the external electric field appears. As the electric field is turned on at the same time of the photoexcitation, the strength of the electric field dominates whether an exciton can form or not. As the external electric field is introduced some pico-seconds after the photoexcitation, a stable exciton can form in the organic polymer chain. Such an exciton cannot be dissociated unless the external electric field is greater than 1 MV/cm, in agreement with experimental results.